Tabs vs Spaces

The debate about using tabs or spaces for indenting code. Which to use?

Tabs.

This is, after all, pretty much what tabs were invented for. On top of that using spaces have the following problems:

They require too many for decent indentation. As in, at least 2 spaces per indentation level.

They make it harder to change the level of indentation.

Indenting and outdenting is slower.

They add unnecessary bulk to the character count. (Important for things like HTML.)

The only decent argument I heard against tabs is that they're often too large (such as equivalent to 8 spaces). My response to this: I never realised we were meant to cater to Notepad users! Seriously, do you just not know how to adjust the tab display size in your editor?

As for the even more important debate about many spaces a tab should be: